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Improving Flow Distribution In Small-Scale Water-Supply Systems Through The Use Of Flow-Reducing Discs And Methods For Analyzing The Effectiveness Of Solar Powered Pumping For A Drinking Water Supply In Rural Panama, Briana I. Drake

Dissertations, Master's Theses and Master's Reports - Open

As continued global funding and coordination are allocated toward the improvement of access to safe sources of drinking water, alternative solutions may be necessary to expand implementation to remote communities.

This report evaluates two technologies used in a small water distribution system in a mountainous region of Panama; solar powered pumping and flow-reducing discs. The two parts of the system function independently, but were both chosen for their ability to mitigate unique issues in the community. The design program NeatWork and flow-reducing discs were evaluated because they are tools taught to Peace Corps Volunteers in Panama.

Even when ample water …

Water Use And System Reliability Under Dieselgenerator And Solar Photovoltaic Powered Pumping Systems: A Case Study Of Solla Togo, Alicia R. Sherrin

Dissertations, Master's Theses and Master's Reports - Open

Access to improved potable water sources is recognized as one of the key factors in improving health and alleviating global poverty. In recently years, substantial investments have been made internationally in potable water infrastructure projects, allowing 2.3 billion people to gain access to potable water from 1990-2012. One such project was planned and installed in Solla, Togo, a rural village in the northern part of the country, from 2010-2012. Ethnographic studies revealed that, while the community has access to potable water, an estimated 45% of the village’s 1500 residents still rely on unprotected sources for drinking and cooking. Additionally, inequality …

Low Impact Development (Lid) Opportunities In The District Of Lamúd, Perú: A Study Of Hydrology, Costs And Maintenance Of Appropriate Stormwater Best Management Practices (Bmps), Olga M. Cano

Dissertations, Master's Theses and Master's Reports - Open

The study aims at identifying opportunities to implement Low Impact Development (LID) Best Management Practices (BMPs) for stormwater management, in the District of Lámud, Perú. Other studies have noted the importance of appropriate stormwater management as part of urban development in developing countries.

Environmental, economic and social aspects were analyzed to identify the most appropriate case. Stormwater Management Model (SWMM) 5.1, was used to obtain runoff results. Ten case scenarios were set up with LID BMP combinations of infiltration trenches, vegetated swales, and retention ponds. Water Environment Research Foundation (WERF) life cost models were used as a reference to calculate …

Evaluating The Potential For Passive Greywater Irrigation In Northern Ghana, Chelsea L. Fagan

Dissertations, Master's Theses and Master's Reports - Open

Water scarcity, malaria, and malnutrition are all concerns facing the people of Chirifoyili and the Northern Region of Ghana. Greywater pooling outside of homes increases human exposure to pathogens and provides breeding grounds for disease carrying insects, especially malaria spreading mosquitoes. This project looks at draining this water away from the home and using it to irrigate vegetables, fruit trees and other beneficial plants.

The purpose of this study is to estimate the effects of greywater irrigation on the growth of plants commonly found in village home gardens. The field project consisted of constructing and managing household greywater irrigation systems …

The Use Of Jatropha Curcas To Achieve A Self Sufficient Water Distribution System: A Case Study In Rural Senegal, Alexandra Archer

Dissertations, Master's Theses and Master's Reports - Open

The use of Jatropha curcas as a source of oil for fueling water pumps holds promise for rural communities struggling to achieve water security in arid climates. The potential for use in developing communities as an affordable, sustainable fuel source has been highly recommended for many reasons: it is easily propagated, drought resistant, grows rapidly, and has high-oil-content seeds, as well as medicinal and economic potential. This study uses a rural community in Senegal, West Africa, and calculates at what level of Jatropha curcas production the village is able to be self-sufficient in fueling their water system to meet drinking, …

Stabilization Of Iron Mine Tailings Through Microbially Induced Calcite Precipitation, Noah D. Buikema

Dissertations, Master's Theses and Master's Reports - Open

Mine tailings are deposited into large-scale impoundments. Seasonal temperature fluctuations destabilize particles on the impoundment surface. Wind-induced shear stresses on the destabilized particles can in turn result in suspension of micron-sized particles into the atmosphere, creating dust storms that pose hazards to humans and the environment. Thus, efficient and sustainable methods of dust abatement are needed. One novel method for controlling dust emissions is biomodification. For example, Sporosarcina pasteurii can promote biocalcification in soil via ureolysis. However, application of this method to fined grained materials, such as mine tailings, is challenging. The goal of this work was to perform a …

A Sub-Basin Water Resource Quantification And Aquifer Productivity Assessment For The Northwest Borehole Scheme Near Opuwo, Namibia, Lucas C. Moilanen

Dissertations, Master's Theses and Master's Reports - Open

Namibia is the most arid country in southern Africa, and is classified as experiencing medium-water stress from 2010-2014 by the Water Resources Institute (WRI) (World Bank, 2015) (Gassert, 2013). Increased water-resources management responsibility at the municipal level, population growth and urbanization trends necessitate community-scale quantification of water resources.

An annual water balance for the contributing sub-basin to Opuwo, Namibia was performed. The Behnke and Maxey method was used to estimate PET, and the methodology outlined by Allen, et al was used to determine soil moisture response to individual rainfall events for one hypothetical year. Water balance results indicate that of …

Application Of Hydrodynamic Models In Simulating The Thermal Regime Of Lake Superior, Rasika K. Gawde

Dissertations, Master's Theses and Master's Reports - Open

In large systems, such as the Great Lakes and coastal oceans, physical processes have a significant influence on chemical and biological phenomena. Hydrodynamic modeling assists in describing these physical characteristics and in recent years, these models have been extensively applied in the Great Lakes basin to study the response of the lake ecosystem to long-term meteorological forcing conditions.

Due to its role in mediating physical, biological and chemical processes in lake environments, water temperature (and the attendant thermal regime) has been the parameter of interest in many of these mathematical modeling studies and was adopted as the primary metric for …

Assessment Of Flood Risk Under Future Climate Conditions, Kaye M. Lafond

Dissertations, Master's Theses and Master's Reports - Open

Global climate change is predicted to have impacts on the frequency and severity of flood events. In this study, output from Global Circulation Models (GCMs) for a range of possible future climate scenarios was used to force hydrologic models for four case study watersheds built using the Soil and Water Assessment Tool (SWAT). GCM output was applied with either the "delta change" method or a bias correction. Potential changes in flood risk are assessed based on modeling results and possible relationships to watershed characteristics. Differences in model outputs when using the two different methods of adjusting GCM output are also …

Improvements In Sustainability Of Gravity-Fed Water Systems In The Comarca Ngäbe-Buglé, Panama: Spring Captures And Circuit Rider Model, Erica Kathryn Jones

Dissertations, Master's Theses and Master's Reports - Open

Gravity-flow aqueducts are used to bring clean water from mountain springs in the Comarca Ngäbe-Buglé, Panama, to the homes of the indigenous people who reside there. Spring captures enclose a spring to direct the flow of water into the transmission line. Seepage contact springs are most common, with water appearing above either hard basalt bedrock or a dense clay layer. Spring flows vary dramatically during wet and dry seasons, and discharge points of springs can shift, sometimes enough to impact the capture structure and its ability to properly collect all of the available water.

Traditionally, spring captures are concrete boxes. …

Tank Sizing And Optimizing Loop Placement In A Branched Water Distribution System, Colin G. Mccorkle

Dissertations, Master's Theses and Master's Reports - Open

More than eighteen percent of the world’s population lives without reliable access to clean water, forced to walk long distances to get small amounts of contaminated surface water. Carrying heavy loads of water long distances and ingesting contaminated water can lead to long-term health problems and even death. These problems affect the most vulnerable populations, women, children, and the elderly, more than anyone else. Water access is one of the most pressing issues in development today.

Boajibu, a small village in Sierra Leone, where the author served in Peace Corps for two years, lacks access to clean water. Construction of …

Characterizing And Improving Production Of Fermentable Sugars And Co-Products From A Forest Product Industry Wastewater Stream, Jifei Liu

Dissertations, Master's Theses and Master's Reports - Open

Hardboard processing wastewater was evaluated as a feedstock in a bio refinery co-located with the hardboard facility for the production of fuel grade ethanol. A thorough characterization was conducted on the wastewater and the composition changes of which during the process in the bio refinery were tracked. It was determined that the wastewater had a low solid content (1.4%), and hemicellulose was the main component in the solid, accounting for up to 70%. Acid pretreatment alone can hydrolyze the majority of the hemicellulose as well as oligomers, and over 50% of the monomer sugars generated were xylose. The percentage of …

Modeling Dynamics Of Ozone And Nitrogen Oxides At Summit, Greenland With A 1-D Process-Scale Model, Keenan Anton Murray

Dissertations, Master's Theses and Master's Reports - Open

This work presents a 1-D process scale model used to investigate the chemical dynamics and temporal variability of nitrogen oxides (NO_x) and ozone (O₃) within and above snowpack at Summit, Greenland for March-May 2009 and estimates surface exchange of NO_x between the snowpack and surface layer in April-May 2009. The model assumes the surface of snowflakes have a Liquid Like Layer (LLL) where aqueous chemistry occurs and interacts with the interstitial air of the snowpack. Model parameters and initialization are physically and chemically representative of snowpack at Summit, Greenland and model results are compared to …

Assessment Of Seismic Damage Of Buildings And Related Environmental Impacts, Carley A. Feese

Dissertations, Master's Theses and Master's Reports - Open

Sustainable development has only recently started examining the existing infrastructure, and a key aspect of this is hazard mitigation. To examine buildings under a sustainable perspective requires an understanding of a building's life-cycle environmental costs, including the consideration of associated environmental impacts induced by earthquake damage. Damage repair costs lead to additional material and energy consumption, leading to harmful environmental impacts. Merging results obtained from a seismic evaluation and life-cycle analysis for buildings will give a novel outlook on sustainable design decisions. To evaluate the environmental impacts caused by buildings, long-term impacts accrued throughout a building's lifetime and impacts associated …

A Hydro-Climatic Modeling Framework For Adaptive Water Resources Management In The Great Lakes Basin, Rabi Gyawali

Dissertations, Master's Theses and Master's Reports - Open

This dissertation addresses water resources decision making in the Great Lakes Basin by developing a multi-model framework for climate change impact assessment, including integrated climate and hydrologic modeling. Physically based watershed models, using soil moisture accounting and temperature index (degree-day) snowmelt algorithms, are developed, calibrated and validated to simulate baseflow, snowmelt, and surface runoff under historic conditions. Comparison with an existing model of the Great Lakes basin, the NOAA Large Basin Runoff Model (LBRM), showed improvements resulting from the increased spatial resolution and use of a more process-based snow algorithm in the Hydrologic Engineering Center's Hydrologic Modeling System (HECHMS). As …

Evaluation Of Non-Stationarity In Annual Maximum Flood Series Of Moderately Impaired Watersheds In The Upper Midwest And Northeastern United States, Neila Salvadori

Dissertations, Master's Theses and Master's Reports - Open

United States federal agencies assess flood risk using Bulletin 17B procedures which assume annual maximum flood series are stationary. This represents a significant limitation of current flood frequency models as the flood distribution is thereby assumed to be unaffected by trends or periodicity of atmospheric/climatic variables and/or anthropogenic activities. The validity of this assumption is at the core of this thesis, which aims to improve understanding of the forms and potential causes of non-stationarity in flood series for moderately impaired watersheds in the Upper Midwest and Northeastern US. Prior studies investigated non-stationarity in flood series for unimpaired watersheds; however, as …

A Novel Approach To Carbon Dioxide Capture And Storage, Brett P. Spigarelli

Dissertations, Master's Theses and Master's Reports - Open

The novel approach to carbon capture and storage (CCS) described in this dissertation is a significant departure from the conventional approach to CCS. The novel approach uses a sodium carbonate solution to first capture CO₂ from post combustion flue gas streams. The captured CO₂ is then reacted with an alkaline industrial waste material, at ambient conditions, to regenerate the carbonate solution and permanently store the CO₂ in the form of an added value carbonate mineral. Conventional CCS makes use of a hazardous amine solution for CO₂ capture, a costly thermal regeneration stage, and the underground storage …

Stilling Basin Scour Remediation Using Air Injection And Flat Plate Extension, Rachael Barlock

Dissertations, Master's Theses and Master's Reports - Open

The South Florida Water Management District (SFWMD) is responsible for managing over 2500 miles of waterways and hundreds of water control structures. Many of these control structures are experiencing erosion, known as scour, of the sediment downstream of the structure. Laboratory experiments were conducted in order to investigate the effectiveness of two-dimensional air diffusers and plate extensions (without air injection) on a 1/30 scale model of one of SFWMD gated spillway structures, the S65E gated spillway. A literature review examining the results of similar studies was conducted. The experimental design for this research was based off of previous work done …

Post-Project Assessment Of Pit Latrines In Rural Panama, Jacob B. Midkiff

Dissertations, Master's Theses and Master's Reports - Open

In Panama, one of the Environmental Health (EH) Sector’s primary goals is to improve the health of rural Panamanians by helping them to adopt behaviors and practices that improve access to and use of sanitation systems. In complying with this goal, the EH sector has used participatory development models to improve hygiene and increase access to latrines through volunteer managed latrine construction projects. Unfortunately, there is little understanding of the long term sustainability of these interventions after the volunteers have completed their service. With the Peace Corps adapting their Monitoring, Reporting, and Evaluation procedures, it is appropriate to evaluate the …

Development Of A 2-Dimensional Finite Volume Model To Assess Hydrodynamic And Microbial Controls On Dnapl Dissolution And Detoxification, Eric S. Wesseldyke

Dissertations, Master's Theses and Master's Reports - Open

Tetrachloroethene (PCE) and trichloroethene (TCE) form dense non-aqueous phase liquids (DNAPLs), which are persistent groundwater contaminants. DNAPL dissolution can be "bioenhanced" via dissolved contaminant biodegradation at the DNAPL-water interface. This research hypothesized that: (1) competitive interactions between different dehalorespiring strains can significantly impact the bioenhancement effect, and extent of PCE dechlorination; and (2) hydrodynamics will affect the outcome of competition and the potential for bioenhancement and detoxification. A two-dimensional coupled flowtransport model was developed, with a DNAPL pool source and multiple microbial species. In the scenario presented, Dehalococcoides mccartyi 195 competes with Desulfuromonas michiganensis for the electron acceptors PCE and …

Terpene And Terpenoid Emissions And Secondary Organic Aerosol Production, Rosa M. Flores

Dissertations, Master's Theses and Master's Reports - Open

Approximately 90% of fine aerosol in the Midwestern United States has a regional component with a sizable fraction attributed to secondary production of organic aerosol (SOA). The Ozark Forest is an important source of biogenic SOA precursors like isoprene (> 150 mg m^-2 d^-1), monoterpenes (10-40 mg m^-2 d^-1), and sesquiterpenes (10-40 mg m^-2d^-1). Anthropogenic sources include secondary sulfate and nitrate and biomass burning (51-60%), vehicle emissions (17-26%), and industrial emissions (16-18%). Vehicle emissions are an important source of volatile and vapor-phase, semivolatile aliphatic and aromatic hydrocarbons that are important …

Free Troposphere Ozone And Carbon Monoxide Over The North Atlantic For 2001-2011, Aditya Kumar

Dissertations, Master's Theses and Master's Reports - Open

Carbon Monoxide (CO) and Ozone (O3) are considered to be one of the most important atmospheric pollutants in the troposphere with both having significant effects on human health. Both are included in the U.S. E.P.A list of criteria pollutants. CO is primarily emitted in the source region whereas O3 can be formed near the source, during transport of the pollution plumes containing O3 precursors or in a receptor region as the plumes subside. The long chemical lifetimes of both CO and O3 enable them to be transported over long distances. This transport is important on continental scales as well, commonly …

Integrated Assessment Of Anthropogenic, Climate, And Policy Induced Changes Of Phosphorus Export In The United States Laurentian Great Lakes Watersheds, Meredith Ballard Labeau

Dissertations, Master's Theses and Master's Reports - Open

Anthropogenic activities have increased phosphorus (P) loading in tributaries to the Laurentian Great Lakes resulting in eutrophication in small bays to most notably, Lake Erie. Changes to surface water quality from P loading have resulted in billions of dollars in damage and threaten the health of the world’s largest freshwater resource. To understand the factors affecting P delivery with projected increasing urban lands and biofuels expansion, two spatially explicit models were coupled. The coupled models predict that the majority of the basin will experience a significant increase in urban area P sources while the agriculture intensity and forest sources of …

Improving The Reliability Of Aquatic Biogeochemical Models: Integrating Information And Optimizing Complexity, Cory P. Mcdonald

Dissertations, Master's Theses and Master's Reports - Open

No abstract provided.

Water Resources, Health, And The Sustainability Of Interventions To Achieve Water And Sanitation Targets Of The Millennium Development Goals In A Changing World, Lauren M. Fry

Dissertations, Master's Theses and Master's Reports - Open

This dissertation addresses sustainability of rapid provision of safe water and sanitation required to meet the Millennium Development Goals. Review of health-related literature and global statistics demonstrates engineers' role in achieving the MDGs. This review is followed by analyses relating to social, environmental, and health aspects of meeting MDG targets.

Analysis of national indicators showed that inadequate investment, poor or nonexistent policies and governance are challenges to global sanitation coverage in addition to lack of financial resources and gender disparity. Although water availability was not found to be a challenge globally, geospatial analysis demonstrated that water availability is a potentially …

Nitrogen Removal And Sustainability Of Vertical Flow Constructed Wetlands For Small Scale Wastewater Treatment, Valerie J. Fuchs

Dissertations, Master's Theses and Master's Reports - Open

The challenge for wastewater professionals is to design and operate treatment processes that support human well being and are environmentally sensitive throughout the life-cycle. This research focuses on one technology for small-scale wastewater treatment: the vertical flow constructed wetland (VFCW), which is herein investigated for the capacity to remove ammonium and nitrate nitrogen from wastewater. Hydraulic regime and presence/absence of vegetation are the basis for a three-phase bench scale experiment to determine oxygen transfer and nitrogen fate in VFCWs. Results show that 90% NH4+-N removal is achieved in aerobic downflow columns, 60% NO3--N removal occurs in anaerobic upflow columns, and …

Long-Range Pollution Transport: Trans-Atlantic Mechanisms And Lagrangian Modeling Methods, Robert Christopher Owen

Dissertations, Master's Theses and Master's Reports - Open

Over the past several decades, it has become apparent that anthropogenic activities have resulted in the large-scale enhancement of the levels of many trace gases throughout the troposphere. More recently, attention has been given to the transport pathway taken by these emissions as they are dispersed throughout the atmosphere. The transport pathway determines the physical characteristics of emissions plumes and therefore plays an important role in the chemical transformations that can occur downwind of source regions. For example, the production of ozone (O₃) is strongly dependent upon the transport its precursors undergo. O₃ can initially be formed …

Development Of Measurement And Modeling Techniques To Quantify Atmospheric Deposition Of Persistent, Bioaccumulative And Toxic Chemicals In The Great Lakes, Mark D. Rowe

Dissertations, Master's Theses and Master's Reports - Open

Measurement and modeling techniques were developed to improve over-water gaseous air-water exchange measurements for persistent bioaccumulative and toxic chemicals (PBTs). Analytical methods were applied to atmospheric measurements of hexachlorobenzene (HCB), polychlorinated biphenyls (PCBs), and polybrominated diphenyl ethers (PBDEs). Additionally, the sampling and analytical methods are well suited to study semivolatile organic compounds (SOCs) in air with applications related to secondary organic aerosol formation, urban, and indoor air quality.

A novel gas-phase cleanup method is described for use with thermal desorption methods for analysis of atmospheric SOCs using multicapillary denuders. The cleanup selectively removed hydrogen-bonding chemicals from samples, including much of …

Nitrogen Oxides In The North Atlantic Troposphere: Impacts Of Boreal Wildfire And Anthropogenic Emissions, Maria Val Martin

Dissertations, Master's Theses and Master's Reports - Open

Nitrogen oxides play a crucial role in the budget of tropospheric ozone (O sub(3)) and the formation of the hydroxyl radical. Anthropogenic activities and boreal wildfires are large sources of emissions in the atmosphere. However, the influence of the transport of these emissions on nitrogen oxides and O sub(3) levels at hemispheric scales is not well understood, in particular due to a lack of nitrogen oxides measurements in remote regions. In order to address these deficiencies, measurements of NO, NO sub(2) and NO sub(y) (total reactive nitrogen oxides) were made in the lower free troposphere (FT) over the central North …

Regulation Issues And Prediction Of Natural Estrogen Loads For Wastewater Treatment Plants, Michelle E. Jarvie

Dissertations, Master's Theses and Master's Reports - Open

No abstract provided.